New technology could prolong the life of medical implants

Blood vessels within a microvascular construct, covering an implanted device

Researchers at the University of Louisville/Jewish Hospital's Cardiovascular Innovation Institute (CII) have discovered a method for preventing scar tissue from forming around implantation devices. This discovery could have a great impact on the functionality of common implanted devices, such as pacemakers, chemotherapy ports and glucose sensors. According to the study, if a unique system of blood vessels is created to interact with local tissue around an implanted device, better long term results can be achieved. The process involves “pre-vascularizing” a device prior to implantation, using what the team call a microvascular construct (MVC), which consists of blood vessels contained within a collagen gel. The idea is that a device will be coated in this gel prior to implantation. Since the body’s natural process is to find a foreign object and form a scar around it, this new study could prevent this problem from occurring.

"Scars have very little blood flow and because this connection between the body and the device is compromised, the function of the device over time can decline, threatening health and leading to additional interventions to replace it" stated Dr. Stuart Williams, scientific director of the CII and a senior investigator on the study.

In tests carried out on animals, the process was successful in providing an environment within the body that does not create scarring. "We found that the presence of the MVCs and collagen altered the way tissue formed around the implants, restricting the formation of scar tissue because there was so much blood vessel activity" Dr. Williams explained. He also added that "the presence of the MVCs and collagen also reduced the number of white blood cells that stimulate inflammation, where the device was implanted."

After the success of these tests, the next challenge for the CII team and Dr. Williams is to design a device that can be effectively used within operating rooms. Once this has been created, Dr. Williams will be able to bring his technology out of the lab and apply it to patients.